TRExp

Spitfire & GT6 Forum

1978 Spitfire 1500 Rear Lowering Block

Moss Motors
AutoShrine Sponsor
AutoShrine Sponsor
AutoShrine Sponsor
AutoShrine Sponsor

B-man Avatar
B-man Brendan Woolrich
Groton, CT, USA   USA
1978 Triumph 1500 "Hers"
I installed a 3/4" thick lowering block today. Purchased from Spit Bits. It was a really easy, straightforward install. Attached are a few pictures. Some tips, tricks and notes:

- the top of the leaf spring is easily accessible through the panel located in front of the fuel tank, under the carpwt. A 5/16 socket is needed to get the screws out.

- the four studs are 5/16-24 thread and are about 4" long. With the nuts on one end, the active length is about 3 1/4". Easily removed with a 9/16 socket (or maybe 5/8)

- once either end of the leaf spring is lifted up by hand or with a jack, the aluminum lowering block can be slid in place. The spring needs to be lifted high enough that the center stud sticking down from the leaf spring will clear the lowering block as it is skid in.

- I had to file and bevel the lower edges of the lowering block so that it would sit into the saddle of the leaf spring. That's a design / manufacturing flaw on the manufacturers part.

- getting the leaf spring center stud to slide into the hole in the lowering block is a little finicky, and a long stick or pipe is helpful to get it in place once the leaf spring is let down off of the back.

- I grabbed four 4" long grade 5 bolts from the hardware store to replace the studs given the extra length needed with the 3/4" block added. Again, starting the threads required some rocking back and forth of the leaf spring.

And that's it. It took less than an hour, including the trip to the hardware store to get the bolts. I don't have "Hers" back down on all 4 yet since I'm doing the front suspension rebuild, with new shorter / stiffer springs. I expect that the block will get rid of the positive camber that resulted from the PO replacement of the leaf spring. And the stance will be similar to that of others.

. Hide banner ads & support this website by becoming a > Gold Supporting Member <

Attachments:
20180414_134023.jpg    42 KB
20180414_134023.jpg

20180414_134507.jpg    23.2 KB
Sign In or Register to view this photo
20180414_141524.jpg    29.4 KB
Sign In or Register to view this photo
20180414_143606.jpg    30.9 KB
Sign In or Register to view this photo
B-man Avatar
B-man Brendan Woolrich
Groton, CT, USA   USA
1978 Triumph 1500 "Hers"
Some more photos


Attachments:
20180414_144517.jpg    53.4 KB
20180414_144517.jpg

20180414_134359.jpg    31.9 KB
Sign In or Register to view this photo
20180414_133507.jpg    36.5 KB
Sign In or Register to view this photo
20180414_134123.jpg    38.9 KB
Sign In or Register to view this photo
Spitfirejoe Avatar
Spitfirejoe Joe Guinan
Fremont, NE, USA   USA
1980 Triumph Spitfire 1500 "The Phoenix"
Good to have the write-up here, thanks.

I use normal Spitfire cylinder head studs instead of bolts. I had a bunch lying around after swapping to ARP hardware, so they were cheap. If you use bolts, make sure you don't thread them in too far as they will hit moving parts inside the differential.



Joe Guinan
Fremont, Nebraska

. Hide banner ads & support this website by becoming a > Gold Supporting Member <
tymnmony Avatar
tymnmony Victor Fleishman
Mississauga, ON, Canada   CAN
So basically all you need to do is place the jack the under the differential. Is that the spot .Then loosen the four bolts. Then slide it in.
I have the lowering block. You make it sound easy. I know there have been other good info on this.

TheZster Avatar
TheZster Steven Z
SAINT LOUIS, MO, USA   USA
1978 Triumph 1500 "BLK-BRY"
In reply to # 1526243 by tymnmony So basically all you need to do is place the jack the under the differential. Is that the spot .Then loosen the four bolts. Then slide it in.
I have the lowering block. You make it sound easy. I know there have been other good info on this.

If you jack differential - you will never get block in....

Jack up vehicle frame - use jackstands to keep it up (you will need your jack again in a minute) .....wheels hanging..... loosen bolts/studs..... remove studs.... Jack up one wheel assembly bit by bit to raise springs off differential.... slide in block... lower wheel assembly enough to put small amount of pressure on spring/block assembly .... locate and finger tighten bolts (which is why you only use a small amount of pressure on spring/block assembly.... they are a tight fit.)..... Lower wheel assembly completely..... tighten bolts/nuts to spec.....

Easy to figure out once you get started...... Keep fingers out from under spring when relying on jack to raise wheel assembly --- I used a long stick to slide block in from the side....

Z

clshore Carter Shore
Beverly Hills, FL, USA   USA
In reply to # 1526248 by TheZster
In reply to # 1526243 by tymnmony So basically all you need to do is place the jack the under the differential. Is that the spot .Then loosen the four bolts. Then slide it in.
I have the lowering block. You make it sound easy. I know there have been other good info on this.

If you jack differential - you will never get block in....

Jack up vehicle frame - use jackstands to keep it up (you will need your jack again in a minute) .....wheels hanging..... loosen bolts/studs..... remove studs.... Jack up one wheel assembly bit by bit to raise springs off differential.... slide in block... lower wheel assembly enough to put small amount of pressure on spring/block assembly .... locate and finger tighten bolts (which is why you only use a small amount of pressure on spring/block assembly.... they are a tight fit.)..... Lower wheel assembly completely..... tighten bolts/nuts to spec.....

Easy to figure out once you get started...... Keep fingers out from under spring when relying on jack to raise wheel assembly --- I used a long stick to slide block in from the side....

Z

The diff is bolted directly to the chassis, and does not move.
So whether you place the jack under the diff or the chassis it does not matter,
as long as you get the car high enough to get rear wheels off the ground and relieve spring pressure.

SpiTazz72 Avatar
SpiTazz72 Bryan H
Magnolia, TX, USA   USA
Great detailed work Brendan!

I don't know what was hung up but I almost lost a finger or two when installing mine and everything seemed to snap into place. Surprisingly all four bolts went straight down into the holes without having to shift things around.
I did take out the rear spring, painted it and put new nyloc nuts on spring retainer brackets then spayed a dry lubricant between the leaves because it had been squeaking.

. Hide banner ads & support this website by becoming a > Gold Supporting Member <
B-man Avatar
B-man Brendan Woolrich
Groton, CT, USA   USA
1978 Triumph 1500 "Hers"
In reply to # 1526243 by tymnmony So basically all you need to do is place the jack the under the differential. Is that the spot .Then loosen the four bolts. Then slide it in.
I have the lowering block. You make it sound easy. I know there have been other good info on this.

Victor, as others have said, you're not jacking up the differential. Once you take the top 4 main bolts out that are holding the top of the leaf spring to the differential, either of the rear brake drums assemblies can be grabbed and lifted up. The center of the leaf spring will then be lifted off of the differential so that the block can be slid in.

Remember, this is a transverse (side to side) leaf spring. It only attaches on top of the differential with those 4 main bolts, and then at each of the rear wheel assemblies, with a single bolt at each.

You would place the jack under one of the rear shock mounts to get the center of the leaf spring to lift off of the differential. Preferably the passenger side since you will have more clearance to get your hand and the block up there. My exhaust was in the way on the drivers side.

And keep in mind that the rear lowering block is really just addressing the rear suspension stance. In general you should only be installing the block in concert with some work on the front suspension as well, which I am also doing. Unless of course you enjoy a nose-high rake!! So even though it is a very easy job to tackle, it's only part of the total job. For scale, I think getting the car up on jack stands and pulling the wheels off is about 40% of the entire job.

Have fun!

B-man Avatar
B-man Brendan Woolrich
Groton, CT, USA   USA
1978 Triumph 1500 "Hers"
In reply to # 1526261 by SpiTazz72 Great detailed work Brendan!

I don't know what was hung up but I almost lost a finger or two when installing mine and everything seemed to snap into place. Surprisingly all four bolts went straight down into the holes without having to shift things around.
I did take out the rear spring, painted it and put new nyloc nuts on spring retainer brackets then spayed a dry lubricant between the leaves because it had been squeaking.

Bryan, you're pointing out something obvious that I didn't say. Installing a lowering block is a great opportunity to replace (or remove and paint) your leaf spring, if needed. Most of the prep and removal is complete at this point, so you might as well. The previous owner of my 78 had replaced the leaf spring and rebuilt the differential, but didn't install a lowering block. This left the car with a very obvious positive camber.

. Hide banner ads & support this website by becoming a > Gold Supporting Member <
spitfire50 Avatar
spitfire50 Paul Mugford
Rochester, N.H., USA   USA
Brendan,
When you finally get the car back on four wheels,, don't forget, you need to reset the toe-in.
All the best,
Paul

B-man Avatar
B-man Brendan Woolrich
Groton, CT, USA   USA
1978 Triumph 1500 "Hers"
In reply to # 1526503 by spitfire50 Brendan,
When you finally get the car back on four wheels,, don't forget, you need to reset the toe-in.
All the best,
Paul

I will have to do some research to figure out how exactly that is done. Thanks for the heads up.

spitfire50 Avatar
spitfire50 Paul Mugford
Rochester, N.H., USA   USA
In reply to # 1526535 by B-man
In reply to # 1526503 by spitfire50 Brendan,
When you finally get the car back on four wheels,, don't forget, you need to reset the toe-in.
All the best,
Paul

I will have to do some research to figure out how exactly that is done. Thanks for the heads up.

Brendan,
Shims at the body mounting brackets for the trailing arms.
All the best,
Paul

B-man Avatar
B-man Brendan Woolrich
Groton, CT, USA   USA
1978 Triumph 1500 "Hers"
In reply to # 1526545 by spitfire50
In reply to # 1526535 by B-man I will have to do some research to figure out how exactly that is done. Thanks for the heads up.
Shims at the body mounting brackets for the trailing arms.

Ah yes. Those shims. I just came across those on the front while installing all new bushings and such up there (will be a separate post) when complete. I will do some reading up on how to check the toe-in and then shim as needed. Another post to be made. Yay! Thanks Paul

. Hide banner ads & support this website by becoming a > Gold Supporting Member <

To add your reply, or post your own questions




Registration is FREE and takes less than a minute!


Having trouble posting or changing forum settings?
Read the Forum Help (FAQ) or contact the webmaster





Join The Club

Sign in to ask questions, share photos, and access all website features

Your Cars

1971 Triumph Spitfire MkIV

Text Size

Larger Smaller
Reset Save

Sponsor Links